PET microplastics in mesophilic anaerobic digestion after thermal-enzyme combined disintegration
Journal of Environmental Chemical Engineering, cilt.14, sa.3, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 14 Sayı: 3
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jece.2026.123108
- Dergi Adı: Journal of Environmental Chemical Engineering
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, INSPEC
- Anahtar Kelimeler: Anaerobic digestion, Microplastics, Pancreatin enzyme, Thermal disintegration, Waste activated sludge
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
Microplastics (MPs) are increasingly found in wastewater treatment plants and can affect the efficiency of anaerobic digestion (AD), since over 90% are retained in waste activated sludge (WAS). Among these, polyethylene terephthalate (PET) is particularly prevalent due to its high density and widespread use. PET are partially susceptible to deterioration under alkaline or enzymatic conditions. This study investigated the fate and impact of PET MPs in AD of WAS following a novel thermal-enzyme (TE) disintegration using pancreatin. The objective was to enhance sludge solubilization and AD efficiency while inducing stress on PET under mesophilic conditions. PET was introduced at doses of 0, 1, 3, 6, and 10 mg/g total solids (TS) to evaluate its influence on methane production, while PET deterioration was assessed by morphological and physicochemical analyses. TE disintegration achieved 51.5% overall disintegration degree (DD) and increased methane yield by 17.6% and improved reactor performance compared with controls. Enhanced hydrolysis and substrate availability promoted higher methane production and improved organic matter degradation, indicating improved reactor stability. PET MP dose had no significant effect on methane production or AD performance. Morphological analyses revealed surface peeling, edge openings, and 40% mass loss in PET MPs following disintegration. Although crystalline structure remained unchanged, a 31.1% decrease in carbonyl index (CI) was observed after disintegration, indicating induced surface oxidation. TE disintegration thus offers a sustainable strategy to enhance AD and improve performance. While minimal changes in crystallinity suggest long-term environmental persistence, the observed surface oxidation possibly makes MPs available for sorption of contaminants.